The present invention relates to an automated navigational charting system for use with the Digital Nautical Chart database developed by the National Imagery and Mapping Agency. More specifically, but without limitation thereto, the present invention relates to a computer program for displaying nautical chart information corresponding to ownship position data from the Global Positioning System.
A traditional method for ship navigation is to plot information on a paper nautical chart on the bridge, and in the Navy's case, in the Combat Information Center. The information is collected from visual observation, reports by other members of the crew, readings from navigation systems onboard, e.g. GPS ownship position in latitude and longitude, range and bearings observed by watchstanders, dead reckoning data including speed and heading, and other information. The date recorded on the paper chart is often subject to interpretation by the navigator and is subject to human error in collecting or recording data. The traditional navigation method therefore suffers the disadvantages of being labor intensive, requiring extensive training, and being subject to human error.
Currently available electronic charts are typically raster scanned paper charts that have limited resolution, and generally require operator input of reference points and ownship position.
A need therefore exists for an automated navigation system that offers greater accuracy and reliability than current methods afford.